Side by side

Citizen Atomic Perpetual A-TvsSeestern S450 Ocean Star

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

S450 Ocean Star
SeesternS450 Ocean Star
MSRP $299
What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Citizen Atomic Perpetual A-T

Owners widely praise the Citizen Atomic Perpetual A-T for its handsome appearance, solid fit and finish, comfortable bracelet, and intuitive world time function. Its perpetual calendar and atomic timekeeping are highlighted as major conveniences, maintaining accuracy within 0.5 seconds even without syncing, and owners appreciate its "set & forget" nature and solar charging. The watch features a modest, stylish blue dial with delicate design details and a clutter-free layout, along with high water resistance without a screw-down crown and light titanium construction. Some find the dial unnecessarily busy, and its time zone functionality is noted as less useful outside the US, with atomic sync being less compelling below the equator. Accuracy is reported as +/-15 seconds per month if not syncing, but +/-0 seconds if it syncs via radio signal. Some find the watch a bit on the large side.

Seestern S450 Ocean Star

Owners widely praise the Seestern S450 Ocean Star's Yachtmaster-style case and flawless bracelet finishing, with one owner noting the ST2130 movement keeps good time. The bezel action is described as having individual notches but feeling like a friction bezel, while another owner flags the bezel and crown action as smooth with perfect alignment. Lume is a point of contention, with one source describing it as a nice cool blue with ice-white application, while others note it as weak or not matching Prospex standards, despite using BGW-9. The watch is considered a "big boy" ideal for larger wrists (19cm+), potentially too large for 17cm wrists due to its size and non-tapering bracelet. Overall, owners rate the Seestern S450 Ocean Star highly for its build quality and finishing at the price point, despite some reservations about its size and lume intensity.

At a glance

15 of 29 specs differ
Diameter
Atomic Perpetual A-T41mm
S450 Ocean Star40mm
Power Reserve
Atomic Perpetual A-T40h
S450 Ocean Star41h
Water Resistance
Atomic Perpetual A-T200m
S450 Ocean Star100m
MSRP
Atomic Perpetual A-T
S450 Ocean Star$299

Full specifications

Case

5 specs
Category
Pilot
Diver
Diameter
41mm
40mm
Lug-to-Lug
46mm
48mm
Material
Stainless Steel
316L Stainless Steel
Water Resistance
200m
100m

Crystal & Dial

3 specs
AR Coating
Underside
Inner
Dial Color
Blue
White
Lume
None
Tritium

Movement

6 specs
Caliber
H800
TMI NH35A
Type
Solar
Automatic
Beat Rate
28,800 vph
21,600 vph
Power Reserve
40h
41h
Jewels
25
24
Complications
None
GMT, Date

Pricing

1 specs
MSRP
$299
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